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One more job to sort out. Ever since i've had the car it's pulled to the right when braking hard. I have had a local mechanic look at it who works on old Rolls Royces and he stopped the pulling to the right considerably and told me he followed a bendix adjusting system. I am still not happy with the pulling and would like to try to improve it to pull straight. Is there a manual available anywhere that details the blow by blow procedure for the correct adjustment.
Thanks
Terry

There is a very detailed procedure for brake adjustment in the Service Letters. I believe those pages are available here but if not, let me know and I'll scan and post. The procedure gives excellent results if followed. Certainly you should be able to achieve perfect equalization, it should stop dead-straight even with your hands off the wheel (not recommended!).

The way I have occasionally fine-tuned my adjustment after going thru the Service Letter procedure is, with the wheels off the ground, I use a pedal jack or the parking brake and partially apply the brakes in increments, then going around to each wheel to feel the drag and adjust individual wheels if necessary. It takes a bit of patience.

Not that it applies if you are pulling to the right, but do you have the narrower brake linings on the front left wheel as specified?

EDIT - one last thought. How long since your mechanic did his adjustment? If it's recent, perhaps you might give it a bit more time. Here's why - with mechanical Bendix brakes, once one set of shoes is firmly applied against the drum, no further movement of the other wheel shoes which may be only in partial contact can be made as the linkage is essentially held against further motion by the shoes in first contact. Thus, the lining on the wheel that gives first contact will be the fastest to wear and at some point they will become equalized assuming the adjustment was reasonably close in the first place.

I presume you've checked or will check for grease on the linings? Those seals with the outer sealing lip can be a bit of a challenge.

hi Dave,

Thanks for the prompt reply. I have found the service letters but unfortunately they are not very clear. The mechanic did the adjustment about 9 months ago.What is the difference between the brake shoe widths for either side?
I don't know if there is any grease on the shoes as I have not personally seen inside the drums. I can't get to them myself yet without some help from my nephew who also likes to help on the car maintenance but will not be visiting until July.
Terry

To compensate for possible movement of the trunnion block (rear of front left spring) during hard braking, front left linings should be 1-3/4 wide, all others 2-1/4 wide.

Not sure what you mean't by the Service Letter instructions being not clear - did you mean it was a bad reproduction that you had trouble reading, or that the instructions themselves weren't clear? If the former, I'll post them again here in this thread.

Here they are - hope the copy quality is OK.

PS - have your mechanic check to make sure the conduit ends are snug in their retainers, the cables themselves aren't frayed, and that the cams, levers, shoe tips, etc. don't show excessive wear - any of these could cause erratic application. See the note about lubricating the conduits and cables (which I did on my front brakes last year and am about to do on the rears this month).

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Sorry about the ambiguity Dave it was the former.

Dave, I had a good opportunity this weekend gone to have a go at the 34's brakes. Nothing serious immediatly amiss but still went through the procedure as per service letter instructions. The left side front did not have the 1.750" width shoes you stated but as elswhere 2.250". Does this matter a great deal? On the test run she still pulls to the left but not so severely. Any further comments would be appreciated please. Will probably go for a brake re-line in the New Year as they are getting near there sell by date.

I'm about to undertake a full brake adjustment, as I am cutting the drums on the 34 Rollston. I'll let you know how I make out.

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Dave, thats an interesting statement. Why would the linings be different on the front left wheel?

Hi Tom,

Any further info on this subject will be good. Even with all Dave's info and advice I still havn't cured the problem completely on my 34. Therefore what you come up with may show something I've missed.

Good luck

Terry

kts68 said Dave, thats an interesting statement. Why would the linings be different on the front left wheel?

Models with the trunnion block at the rear shackle of the front left spring required narrower linings on that wheel than the others. Reason: since the rear shackle is not fixed in position but can float slightly due to the trunnion, extremely hard brake application would let the entire front axle on the left side move rearwards ever so slightly but enough to add to the cable brake tension and hence the brake force in that wheel.

I don't recall just when the trunnion block was adopted, the 8th series I think.